1. Field of the Invention
The present invention relates to a multilayer electronic component, such as a laminated inductor, and a manufacturing method therefor.
2. Description of the Related Art
A conventional multilayer electronic component has a known structure in which a terminal electrode is formed at each end of a rectangular parallelepiped laminate. The multilayer electronic component is manufactured as follows: initially, ceramic green sheets are laminated so that a laminate of the sheets is formed. Then, the laminate of the sheets is cut to have a size of each of unit components. Then, each of the cut laminates of the sheets are baked and polished so that a laminate is obtained. Finally, a terminal electrode is formed at each end of the laminate so that a multilayer electronic component is manufactured.
A direction in which the green sheets are laminated is a direction perpendicular to a direction in which the two terminal electrode are connected to each other. However, the directions of internal electrodes of a multilayer electronic component of the foregoing type cannot be made constant, causing the characteristics of the multilayer electronic component to be instable. The foregoing fact becomes conspicuous especially for a laminated inductor which is an example of the multilayer electronic component.
Therefore, multilayer electronic components have appeared in recent years, each of which incorporates green sheets laminated in a direction in parallel with a direction of the connection between the terminal electrodes. A laminated inductor which is an example of the multilayer electronic component of the foregoing type will now be described. The laminated inductor is formed by laminating a green sheet having an internal conductor to be formed into a coil, and a green sheet having lead electrodes for establishing the connection between the internal conductor and a terminal electrode. Each green sheet has a via hole filled with a conductor for establishing the connection. Thus, the green sheets are electrically conducted to each other through the via holes. In the foregoing laminated inductor, the direction of the magnetic flux is in parallel to a direction in which the terminal electrodes are connected to each other. That is, the terminal electrodes are formed at two ends of the laminate in the direction of lamination. Therefore, the direction of the magnetic flux after a mounting operation is always in parallel with the surface of mounting. As a result, stable characteristics can be obtained.
However, the lead conductor of the laminated inductor cannot easily be formed. That is, the laminated inductor has the lead conductor which extends substantially straight from the internal conductor to the terminal electrode. Therefore, when the green sheets are laminated, a conductor for establishing the connection is undesirably deviated by a stress. Thus, the electrical conduction between the internal conductor and the terminal electrode is sometimes disconnected. The laminated inductor is formed such that the direction in which the terminal electrodes are connected to each other and that of the magnetic flux are in parallel with each other. Therefore, a larger number of green sheets must be laminated as compared with the conventional multilayer electronic component. Therefore, long time is required to complete the laminating process, thus causing the productivity to deteriorate. What is worse, the laminated inductor sometimes encounters a fact that a required shape cannot always be obtained because burrs and/or breakage occur, in particular, at two ends of the laminated inductor when the laminate is polished. As described above, the foregoing laminated inductor has been suffered from unsatisfactory manufacturing yield.